Natural Gas Our New Savior? Not So Fast . . .

Remember how ethanol was going to save us? It was the perfect solution to not one, but two different problems. The first was energy security: since it’s a type of alcohol distilled from home-grown corn, ethanol would replace the gasoline made from oil imported from Bad People in places like Iran. The second was climate change. Ethanol emits heat-trapping CO2 like gasoline does, but the corn sucks in CO2 while it’s growing, so it’s mostly a wash.

That was the sales pitch, anyway, and for a while, lots of people bought it. The Federal government subsidized ethanol production, and an EPA regulation requiring the use of renewable fuels boosted ethanol’s stock still further. Then scientists began calculating the actual climate impact of corn ethanol, and discovered it wasn’t much better than gas — and might actually be worse.

You’d think we’d have learned something from this cautionary tale. Evidently not, though: we have a new savior called natural gas. It’s the perfect solution, because it’s plentiful and home-drilled, (thank you, fracking), and it emits only half the CO2 that coal does. If we could replace our current coal-fired power plants with gas plants, it wouldn’t solve the problem of climate change, but it would buy us time to shift over to true renewables like wind and solar.

You know what’s coming next, right? I’m afraid so. Just as happened with ethanol, scientists and engineers are starting to take a more serious look at natural gas, and the story turns out to be more complicated and less ideal than it originally seemed. First, the good news: natural gas emits drastically less soot and other particulates than coal. Soot is bad for the lungs, and it contributes to global warming all by itself, so cutting back on it would clearly be a good thing.

And if you could magically flip a switch and turn all existing coal plants in to gas plants, you would indeed cut CO2 emissions significantly.

But there is no magic switch, and therein, according to a recent analysis published in Environmental Research Letters, lies a problem. “The most surprising thing we found,” lead author Nathan Myhrvold told me recently, “is that unless you switch to a form of energy that cuts emissions really drastically” — and he isn’t talking about any piddling 50%, either — “you basically don’t get any real effect.” (If you recognize Myhrvold’s name, it might be because he used to be a top executive at Microsoft, or it might be from his exploits as a barbecue champion or as a donor to the Search for Extraterrestrial Intelligence — but he also holds a degree in theoretical physics from Princeton.)

His point, and that of his co-author Ken Caldeira, a climate scientist with the Carnegie Institution of Washington, is that before a new natural-gas power plant can go into operation it’s already made the climate problem worse. It takes energy to build the plant, most of which comes from fossil fuels. The process of drilling for natural gas and piping it to the plant, moreover is prone to leakage — and methane, the main component of natural gas, is itself a powerful greenouse gas . And while the construction is going on, says the Myhrvold-Calderia study, you’re still emitting CO2 from those old, dirty coal plants, which can’t be switched off until the new gas plants are ready to go.

The bottom line that emerges from this “life-cycle analysis,” or LCA, said Myhrvold, is that by the time we could switch from coal to gas, there would already be so much more CO2 and methane in the atmosphere that we’d be much deeper in the hole. “It’s like living on a credit card,” he said. “It’s easy to get into a situation where it will take years and years to pay back.”

In fact, he argues, because CO2 stays in the atmosphere for so long once it’s up there, a switch to natural gas would have zero effect on global temperatures by the year 2100. “If you take 40 years to switch over entirely to natural gas,” he said,

A switch to renewables (true renewables, that is, not corn-based ethanol) would also incur a carbon debt: it takes energy to manufacture solar panels and wind turbines too, after all. If we made that switch, according to Myhrvold and Calderia’s calculations, you wouldn’t see a change in temperatures for decades either. But by 2100, the decrease would start to kick in (he explicitly rejects the idea of new hydropower dams, by the way, whose energy is renewable but which are, he said, “much worse than coal for the first hundred years”: the trees and other vegetation that rot beneath backed-up water release lots of methane).

“You can quibble about LCA numbers,” he said, “and a number of people have emailed us criticizing some of our assumptions. But the main idea is that if you’re transitioning to something that’s only twice as good as coal, it’s not really worth your time. If you’re doing something that’s better by a factor of 10, it’s reasonable.”

What an idiotic argument he is making. Has he not heard of global warming. WE MUST LEAVE ALL COAL IN THE GROUND AND START TODAY. PERIOD

If it takes 4 years to replace al coal with gas then thats the time we must wait, start today. No time to lose.

rajatsen on Tue, 28th Feb 2012 10:04 pm

I am sorry — I don’t get the point. It seems to me the authors are saying that we should stay with coal forever; since — if we let the markets do their thing — coal plants will not be replaced by renewables is the foreseeable future.

If the point is that government must dictate that coal plants must be replaced by renewables — I don’t see that happening — at least in the US.

In my mind using more natural gas and introducing a market based with carbon pricing is the only way a transition happens.

BillT on Wed, 29th Feb 2012 1:24 am

Ah, even the commenters are not awake today. The author is saying that any effort to switch to any other fuels/energy sources will not make a difference in the next 90 years. None. FINALLY, something in print by a real educated person that thinks beyond the ‘renewables’ propaganda. As it is obvious that the world is NOT going to make much of a switch to renewables, it is good to know that it would not make a difference anyway. We are F—-d!

He recognizes that there is more to it than EROEI or cost or ease of use. There is the TOTAL effect on the environment and the actual loss of energy in the process of switching. (Not to mention starvation of the population.) Few here think about the huge existing legacy energy system in the world that was built over the last 100 to 150 years. Do you really think that can be changed to something else in a year? 10? 50? Especially since the cheap, plentiful energy source (oil) used to build it is what is shrinking in supply? No, we don’t have the time or money to make a significant difference. We are screwed by our own poorly educated stupidity and greed.

Kenz300 on Wed, 29th Feb 2012 8:03 pm

Bring on the electric, flex-fuel, hybrid, CNG, LNG and hydrogen fueled vehicles. It is time to end the oil monopoly on transportation fuels. Ethanol is now 10% of our fuel supply. LNG is increasingly being used by the over the road trucking industry. CNG fueled vehicles are being introduced to the market. Every auto maker is coming out with an electric or hybrid vehicle. None of these are a silver bullet but anything we can do to end the oil monopoly on transportation fuels is a step forward. Monopolies are only good for the monopoly. We need choice at the pump. The oil companies and their supporters will do all they can to reduce competition. The windfall profits for oil companies when prices spike are their incentive to crush any competition.